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Oldest material on Earth discovered – BBC News



Scientists analysing a meteorite have discovered the oldest material known to exist on Earth.

They found dust grains within the space rock – which fell to Earth in the 1960s – that are as much as 7.5 billion years old.

The oldest of the dust grains were formed in stars that roared to life long before our Solar System was born.

A team of researchers has described the result in the journal Proceedings of the National Academy of Sciences.

When stars die, particles formed within them are flung out into space. These “pre-solar grains” then get incorporated into new stars, planets, moons and meteorites.

“They’re solid samples of stars, real stardust,” said lead author Philipp Heck, a curator at Chicago’s Field Museum and associate professor at the University of Chicago.

A team of researchers from the US and Switzerland analysed 40 pre-solar grains contained in a portion of the Murchison meteorite, that fell in Australia in 1969.

“It starts with crushing fragments of the meteorite down into a powder,” said co-author Jennika Greer, from the Field Museum and the University of Chicago.

“Once all the pieces are segregated, it’s a kind of paste, and it has a pungent characteristic – it smells like rotten peanut butter.”

This whiffy paste was then dissolved in acid, leaving only the stardust.

“It’s like burning down the haystack to find the needle,” said Philipp Heck.

To work out how old the grains were, the researchers measured how long they had been exposed to cosmic rays in space. These rays are high-energy particles that travel through our galaxy and penetrate solid matter.

Some of these rays interact with the matter they encounter and form new elements. The longer they are exposed, the more of these elements form. The researchers used a particular form (isotope) of the element neon – Ne-21 – to date the grains.

“I compare this with putting out a bucket in a rainstorm. Assuming the rainfall is constant, the amount of water that accumulates in the bucket tells you how long it was exposed,” said Dr Heck.

Measuring how many of the new elements are present tells scientists how long the grain was exposed to cosmic rays. This in turn informs them how old it is.

Some of the pre-solar grains turned out to be the oldest ever discovered.

Based on how many cosmic rays had interacted with the grains, most had to be 4.6-4.9 billion years old. For comparison, the Sun is 4.6 billion years old and the Earth is 4.5 billion.

However, the oldest yielded a date of around 7.5 billion years old.

More to be found

Dr Heck told BBC News: “Only 10% of the grains are older than 5.5 billion years, 60% of the grains are “young” (at) 4.6 to 4.9 billion years old, and the rest are in between the oldest and youngest ones.

“I am sure there are older pre-solar minerals in Murchison and other meteorites, we just haven’t found them yet.”

Previously, the oldest pre-solar grain dated with neon isotopes was around 5.5 billion years old.

The findings shed light on a debate over whether or not new stars form at a steady rate, or whether there are highs and lows in the number of new stars over time.

“Thanks to these grains, we now have direct evidence for a period of enhanced star formation in our galaxy seven billion years ago with samples from meteorites. This is one of the key findings of our study,” said Dr Heck.

The researchers also learned that pre-solar grains often float through space stuck together in large clusters, like granola. “No one thought this was possible at that scale,” Philipp Heck explained.

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How were Supermassive Black Holes Already Forming and Releasing Powerful Jets Shortly After the Big Bang? – Universe Today



In the past few decades, astronomers have been able to look farther into the Universe (and also back in time), almost to the very beginnings of the Universe. In so doing, they’ve learned a great deal about some of the earliest galaxies in the Universe and their subsequent evolution. However, there are still some things that are still off-limits, like when galaxies with supermassive black holes (SMBHs) and massive jets first appeared.

According to recent studies from the International School for Advanced Studies (SISSA) and a team of astronomers from Japan and Taiwan provide new insight on how supermassive black holes began forming just 800 million years after the Big Bang, and relativistic jets less than 2 billion years after. These results are part of a growing case that shows how massive objects in our Universe formed sooner than we thought.

Astronomers have known about SMBHs for over half a century. In time, they came to realize that most massive galaxies (including the Milky Way) have them at their cores. The role they play in the evolution of galaxies has also been the subject of study, with modern astronomers concluding that they are directly related to the rate of star formation in galaxies.

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Similarly, astronomers have found that SMBHs have tight accretion disks around them where gas and dust are accelerated to close to the speed of light. This causes the center of some galaxies to become so bright – what are known as active galactic nuclei (AGNs) – that they outshine the stars in their disks. In some cases, these accretion disks also lead to jets of hot material that can be seen from billions of light-years away.

According to conventional models, galaxies didn’t have enough time to develop central black holes when the Universe was less than a billion years old (ca. 13 billion years ago). However, recent observations have shown that black holes were already forming at the center of galaxies at the time. Addressing this, a team of scientists from SISSA proposed a new model that offers a possible explanation.

For their study, which was led by Lumen Boco – a Ph.D. student from the Institute for Fundamental Physics of the Universe (IFPU) – the team started with the well-known fact that SMBHs grow in the central regions of early galaxies. These objects, the progenitors of elliptical galaxies today, had a very high concentration of gas and an extremely intense rate of new star formation.

The first generations of stars in these galaxies was short-lived and quickly evolved into black holes that were relatively small, but significant in number. The dense gas that surrounded them led to significant dynamic friction and caused them to migrate quickly to the center of the galaxy. This is where they merged to create the seeds of supermassive black holes – which slowly grew over time.

Artist’s impression of the path of the star S2 as it passes very close to the supermassive black hole at the center of the Milky Way. Credit: ESO/M. Kornmesser

As the research team explained in recent SISS press release:

“According to classical theories, a supermassive black hole grows at the centre of a galaxy capturing the surrounding matter, principally gas, “growing it” on itself and finally devouring it at a rhythm which is proportional to its mass. For this reason, during the initial phases of its development, when the mass of the black hole is small, the growth is very slow. To the extent that, according to the calculations, to reach the mass observed, billions of times that of the Sun, a very long time would be required, even greater than the age of the young Universe.”

However, the original mathematical model they developed showed that the formation process for central black holes could be very rapid in its initial phases. This not only offers an explanation for the existence of SMBH seeds in the early Universe but also reconciles the timing of their growth with the known age of the Universe.

In short, their study showed that the process of migration and mergers of early black holes can lead to the creation of an SMBH seed of 10,000 to 100,000 solar masses in just 50-100 million years. As the team explained:

“[T]he growth of the central black hole according to the aforementioned direct accretion of gas, envisaged by the standard theory, will become very fast, because the quantity of gas it will succeed in attracting and absorbing will become immense, and predominant on the process we propose. Nevertheless, precisely the fact of starting from such a big seed as envisaged by our mechanism speeds up the global growth of the supermassive black hole and allows its formation, also in the Young Universe. In short, in light of this theory, we can state that 800 million years after the Big Bang the supermassive black holes could already populate the Cosmos.”

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In addition to proposing a working model for observed SMBH seeds, the team also suggested a method for testing it. On the one hand, there are the gravitational waves that these mergers would cause, which could be identifiable using gravitational wave detectors like Advanced LIGO/Virgo and characterized by the future Einstein Telescope.

In addition, the subsequent development phases of SMBHs is something that could be investigated by missions like the ESA’s Laser Interferometer Space Antenna (LISA), which is expected to launch by around 2034. In a similar vein, another team of astronomers recently used the Atacama Large Millimeter/submillimeter Array (ALMA) to address another mystery about galaxies, which is why some have jets and others don’t.

These fast-moving streams of ionized matter, which travel at relativistic speeds (a fraction of the speed of light), have been observed emanating from the center of some galaxies. These jets have been linked to a galaxy’s rate of star formation because of the way they expel matter that would otherwise collapse to form new stars. In other words, these jets play a role in the evolution of galaxies, much like SMBHs.

For this reason, astronomers have sought to learn more about how black hole jets and gaseous clouds have interacted over time. Unfortunately, it has been difficult to observe these kinds of interactions during the early Universe. Using the Atacama Large Millimeter/submillimeter Array (ALMA), a team of astronomers managed to obtain the first resolved image of disturbed gaseous clouds coming from a very distant quasar.

Reconstructed images of MG J0414+0534, showing emissions from dust and ionized gas around a quasar (red) and carbon monoxide gas (green), which have a bipolar structure along the jets. Credit: ALMA (ESO/NAOJ/NRAO), K. T. Inoue et al.

The study that describes their findings, led by Prof. Kaiki Taro Inoue of Kindai University, recently appeared in the Astrophysical Journal Letters. As Inoue and his colleagues explained, the ALMA data revealed young bipolar jets emanating from MG J0414+0534, a quasar located roughly 11 billion light-years from Earth. These findings show that galaxies with SMBHs and jets existed when the Big Bang was less than 3 billion years old.

In addition to ALMA, the team relied on a technique known as gravitational lensing, where the gravity of an intervening galaxy magnifies light coming from a distant object. Thanks to this “cosmic telescope” and ALMA’s high resolution, the team was able to observe the disturbed gaseous clouds around MG J0414+0534 and determine that they were caused by young jets emanating from an SMBH at the center of the galaxy.

As Kouichiro Nakanishi, a project associate professor at the National Astronomical Observatory of Japan/SOKENDAI, explained in an ALMA press release:

“Combining this cosmic telescope and ALMA’s high-resolution observations, we obtained exceptionally sharp vision, that is 9,000 times better than human eyesight. With this extremely high resolution, we were able to obtain the distribution and motion of gaseous clouds around jets ejected from a supermassive black hole.”

These observations also showed that the gas was impacted where it followed the direction of the jets, causing particles to move violently and become accelerated to speeds of up to 600 km/s (370 mps). What’s more, these impacted gaseous clouds and the jets themselves were much smaller than the size of a typical galaxy at this age.

Artist’s impression of MG J0414+0534, showing the powerful jets that disturb the surrounding gas in the host galaxy. Credit: Kindai University

From this, the team concluded that they were witnessing a very early phase of jet evolution in the MG J0414+0534 galaxy. If true, these observations allowed the team to witness a key evolutionary process in galaxies during the early Universe. As Inoue summarized:

“MG J0414+0534 is an excellent example because of the youth of the jets. We found telltale evidence of significant interaction between jets and gaseous clouds even in the very early evolutionary phase of jets. I think that our discovery will pave the way for a better understanding of the evolutionary process of galaxies in the early Universe.”

Together, these studies demonstrate that two of the most powerful astronomical phenomena in the Universe emerged earlier than expected. This discovery also provides astronomers with the opportunity to explore how these phenomena evolved over time, and the role they played in the evolution of the Universe.

Further Reading: SISSA, ALMA, Astrophysical Journal, Astrophysical Journal Letters

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NASA's webb telescope will shoot a lens into the early universe next year – Designboom



our knowledge of the cosmos will change when NASA launches its $10 billion webb telescope

in exactly one year, NASA‘s james webb telescope — a tennis court-sized telescope covered in honeycomb mirrors — will make its way into space. on it’s list of duties, the device will study the solar system, directly image exoplanets, photograph the first galaxies, and explore the mysteries of the origins of the universe.

image courtesy of NASA/chris gunn

named after james E. webb, a NASA administrator during the apollo era, the webb telescope is a joint venture between NASA, the european space agency (ESA), the canadian space agency (CSA) and space telescope science institute (STSCI). its’ mission is to look back through time to when galaxies were young. webb will do this by observing galaxies that are very distant, at over 13 billion light years away.

our knowledge of the cosmos will change when NASA launches its $10 billion webb telescope

NASA/chris gunn

in order to do so, several innovative technologies have been developed for webb including a primary mirror made of 18 separate segments that unfold and adjust to shape after launch. made of ultra-lightweight beryllium — a metal that can endure extremely heat — this will ensure that the telescope holds its shape across a range of cryogenic temperatures, which is just what it would encounter in space on the webb telescope. this reflective surface will also act as the mirror needed to measure the light from these distant galaxies.

our knowledge of the cosmos will change when NASA launches its $10 billion webb telescope

NASA/MSFC/david higginbotham

the telescope’s four instruments – cameras and spectrometers – have detectors that are able to record extremely faint signals. one instrument (NIRSPEC) has programmable microshutters, which enable observation up to 100 objects simultaneously. webb also has a cryocooler for cooling the mid-infrared detectors of another instrument (miri) to a very cold 7k so they can work.

our knowledge of the cosmos will change when NASA launches its $10 billion webb telescope

NASA/chris gunn

on tuesday, march 30, 2021, webb will launch on a european ariane 5 rocket from the guiana space centre to the northwest of kourou in french guiana. after that, it will observe the universe from the second lagrange point (L2) around a million miles/1.5 million kilometers from earth, sending its images back to earth via NASA’s deep space network.

at least that is the plan. NASA administrator jim bridenstine recently announced that the work on the james webb space telescope had been paused because of the coronavirus crisis. the statement said that both nasa and northrop grumman are ‘suspending integration and testing operations’ on the multi-billion-dollar observatory, which is currently set for some testing at a northrop grumman plant in california.

project info

name: james webb telescope
agency: NASA

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How Sensors can be Used to Detect Oil Spills – AZoCleantech



Image Credit: dimitris_k /

The rapid analysis of oil spills is vital to the success of their clean up. In a paper published earlier this year in the scientific journal Remote Sensing of Environment, a team from Water Mapping, in collaboration with scientists at other institutes across the US and Canada, describes how using multiple remote sensors allows for the rapid estimation of the thickness and nature of oil spills.


The method will likely be implemented to improve future oil spill containment efforts once more testing is carried out.


Collecting Oil-Spill Data is Essential to Clean up Success


Time is important in containing and preventing serious environmental damage from oil spills. Scientists need to gain information regarding the type of oil, its thickness, and the volume of oil that had spilled in order to develop vital strategies to contain the spill.


Currently, satellites play an essential role in spotting oil slicks from above. However, field verification is required in order to confirm the characteristics of the spill. Verification methods are often difficult, impractical, and can risk putting people in unsafe environments.


Now, scientists have developed a way to enhance the efficacy of the measurements taken from satellite images. The method utilizes remote sensing techniques to help improve the accuracy of the analysis of images collected from satellites.


The team tested their method on two on-site field tests. They proved its efficacy in rapidly collected and analyzing data in near-real-time, providing vital information on the characteristics of the spill as fast as possible, allowing tactical response teams to act immediately.


Communicating Oil-Spill Data in Real-Time


Effective cleanups are heavily reliant on receiving accurate data on the spill quickly. Without this, response teams may be sent out to focus on less important areas of the spill, allowing the thicker part of the leak to continue to spread and cause environmental damage.


By utilizing remote sensing, researchers are able to gain information that isn’t available to them with the naked eye. Sensors can sense and report on data from optical, multispectral, microwave, and thermal sources as well as others.


As technology has advanced, sensors have become smaller, meaning that they can now be used on aircraft and drones as well as on satellites. They can even be incorporated into handheld instruments. This gives scientists far more sources of data to give information on the nature of the oil spill.


Information taken from different sources can help scientists in different ways. For example, data collected from satellites can be communicated to first-responders in just a few minutes, whereas vital tactical information can be transmitted from drones in real-time.


Remotely Sensing Oil Spills in Harsh Environments


The method is also vitally useful for gathering information about oil spills located in remote or harsh environments where sending human workers to the site is dangerous. The findings of the new study are important for the future of how “actionable oil” spills (those involving thick and/or emulsified oil) are tackled.


The next steps will be to continue testing the method, gauging how effective it is at collecting data on oil spills in different environments, as well as its efficacy on sensing different kinds of oil spills. Before the method can be adopted at a large scale, scientists must first fully understand how the technologies used by different sensors work with different kinds of oil spills in different environments, particularly at different temperatures.


The team that worked on the current research project aim to expand monitoring with remote sensing as well as with drones and GPS drifters. In addition, they are working in collaboration with NASA to promote the better monitoring of oil spills worldwide.

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